Rock solid battery and MicroUSB-Port


EvilDragon

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Following up the last blogpost where I posted that the battery contacts needed to be realigned, we now received the test PCB with properly placed battery connectors.

1. The optimized battery connection


You can see on this picture that they now are properly aligned to the contact pads on the battery:

BattAlig.jpg

Of course, how it looks like is not important, important is that it is being tested!
So here is Nikolaus test setup:

BattTest.jpg

The test PCB in inside the case, including the battery. And the battery connectors are directly attached to a real working Pyra PCB.
Nikolaus can then test the contacts by checking what the charger chip reports and whether the battery loses contact.

And guess what: It's rock solid!
Charging, discharging is now working properly, no wrong readings anymore!
Nikolaus tried wiggling around the battery as much as he could, but the contact never failed or lost contact.

That's how it's supposed to be!

But on the same test PCB is something else... and that's...


2. The new hole-through MicroUSB-OTG port

While sourcing parts for the Pyra a long time ago, we only found a surface-mount MicroUSB-OTG port.
However, sometime during development, a new hole-through-port has been released - which we just bought and tested on the test PCB.

The port works exactly the same as the old one - however, thanks to the hole-through pins, it's rock solid and you will not be able to break the Micro USB port!
Before you break the port, it's more likely that the cable or even the PCB breaks...

Anyone who ever owned an N900 will surely appreciate that.

Here's a picture. Doesn't that look solid? :)

MicroUSB.jpg

With these two final tests we made, the mainboard can now be finalized and go into production for the prototype run as well!
Now ALL PCBs are finished - and if everything turns out fine, no more revisions or changes are neeeded.



3. The LCD-Cable testing PCB

As reported a while ago, the LCD Cable had some improper connections because I thought the ears were too close to the port?
Well, it turned out that was okay - the cables actually work.

The reason the prototype boards here had connection issues with the LCD cable was something different:
Back in July or August (can't remember the exact date), we received samples of LCD Cables where the stiffener was a bit too thick.
Because of that, it was really hard inserting the cables into the mainboard - but not impossible.

And for GamesCom, these were the only cables we had - so we used them to assemble all the units.

After GamesCom, we received the update cables with proper stiffener - but those didn't work properly, so my first idea were the ears.
But it wasn't! Actually, an original 3M cable (not custom made) we were using with the EVMs also stopped working.
And the one in my unit also stopped working after I unplugged and replugged it a few times.

So... the too-thick stiffener killed the LCD Cable connector!

This is good - because it means we most probably don't need to change the LCD Cable design - which means they would be ready for mass production now!
The connectors on the mainboards will be reworked (no big deal).

However, we want to be sure everything is fine, so we designed this little PCB:

lcdcabletest.jpg

It's not populated yet (will happen tomorrow), but basically, it's a cable loop.
On the PCB, there will be both types of connectors (the one that's on the displayboard and the one that's on the mainboard) and each connection has a test point.

With that, we can simply plug in the LCD Cable, and test each connection with a multimeter so we can be sure both the cable and connectors work fine and don't lose contact easily.

Of course, I'll let you know the results of the LCD Cable test. But if it works fine (as we suspect), we could easily get all the needed LCD cables for the mass production during December.


That's it for today! Moving along with those small tweaks, but I'm happy they work out so well.
 
Ah, those are external power pads on the Pyra mainboard too? That's neat, I had to use them when I was diagnosing a short circuit on my Pandora. However, I note that you also connect the sense pin, so does that mean it doesn't bypass the power circuitry as it does on the Pandora? I liked that because it meant I could pump amps through the rest of the board until the short circuit lit up - if there's a charge controller and all that stuff in there, I'd be afraid I would confuse the hell out of it pumping that current through it at best, if not actually blow something up (most of everything else is connected across the voltage, and doesn't care what current is passing by, although I could have blown one of the traces if I wasn't confident the short would pop first).
 
The first two things you mentioned are awesome, and even the third thing isn't that bad. Is there any reason you can't go with a floppy cable? I just don't want another type of self-destructing cable for the Pyra, although it should be easier to swap out if that is the case.
 
The way I read is is that they are going for the floppy cable, just the stiff cable killed the connectors on some boards. So they'll need to be patched, but in the meantime they made a test board so they can test cables without having fixed boards.

Edit: @rygD
 
You might want to make sure the batteries do not explode, I heard it's bad for business... :D
 
The way I read is is that they are going for the floppy cable, just the stiff cable killed the connectors on some boards. So they'll need to be patched, but in the meantime they made a test board so they can test cables without having fixed boards.

Ahh, I'm sorry, I forgot to explain what the stiffener is:

Most flex cable have stiffener added at the ends. This adds thickness to the cable and makes the end with the contacts more stable and robust.
That's the reason they are less flexible at both ends.

The stiffener also ensures that the cable isn't too thin at the connectors area (otherwise it would fall out or wouldn't make proper contact).

If the stiffener is a tiny bit too thick, doesn't properly fit into the connector... but depending on the thickness, you can still use force to get it in.

Think of a 2m high truck driving under a 1,99m high bridge. Yes, it might get through, but it WILL damage the bridge. Once it has driven through a few times, the bridge might've been damaged enough that you every 2m truck can fit through with ease.

This happened with our connectors. However, the damage the cable causes are at the contact pins... effectively making the connectors useless.
 
Sounds great. Being the pessimist that I am, my guess is still on March 2017 for units to start arriving.
 
Will we have control over the charging process of the battery ?
For example I would like to prevent the battery from charging more than 80% as to increase the lifespan of the battery.
 
@Bokkertoff that would certainly be useful

If we're lucky there might be several ways to achieve this - but being able to use the unit on mains only power leaving the battery alone @ 80% would be great

Did anyone mention (I can't remember) can the Pyra be run on mains without battery?
 
Did anyone mention (I can't remember) can the Pyra be run on mains without battery?
I think aTc's prototype had to do just that for a while as he was having battery alignment issues.
 
I think aTc's prototype had to do just that for a while as he was having battery alignment issues.
well that's good news if worst comes to worst (although I'm not convinced there won't be a better solution) if you know you're going to use the machine on mains for a long while you can manually wait for the charge to reach 80% (or whatever charge you want) then leave the battery out....
 
Sounds great. Being the pessimist that I am, my guess is still on March 2017 for units to start arriving.

I was thinking June myself, but I'm just not letting myself get to excited as I did with the Pandora, as that made for some looooooooooonnnnnnnnnnnggggggggg months leading up to it's release. The further back this appears to be, the better off I'll be. Plus, I've got an ICP2 credit from Link, and I can't use that right away anyways, so I'm on "stand by" either way. LOL

Chris
 
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